GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - MO50QNL5LTW4F114J

The passage implies that political centralization is a feature that A. has not historically tended to emerge in centers with fewer than 20,000 inhabitants B. distinguished other Mississippian chiefdoms from Cahokia C. is considered characteristic of state but not of chiefdoms D. often results from aggressive expansionism and economic specialization E. has historically been necessary for extensive trade to occur